A spindle motor for driving fixed-disc memories is known, for example, from U.S. Pat. No. 5,216,557, which motor comprises a stationary base flange that supports a central spindle. A hub furthermore exists, which is positioned with the aid of suitable bearings, such that it pivots on the spindle and which has at least one fixed-memory disc arranged on it. On the inside circumference, the hub carries a magnetic yoke with a permanent magnet, which constitute a part of the rotor for the spindle motor.
A stator with stator windings is arranged in the standard way opposite the permanent magnet, said stator being attached directly or by means of a fastener to the base flange.
One disadvantage of the above-described, known spindle motor design consists in that the stator is fixedly connected to the base flange, and that whenever current is flowing, vibrations and noises are generated in the stator winding owing to the electromagnetic fields, which are referred to in the following as electromagnetic noises. These noises cause a considerable share of the total spindle motor noise.
When using a spindle motor as drive for fixed-disc memories, it is required that the motor be clean and free of dust. As described in the above, for example, traditional, unprotected stator windings have the additional disadvantage that dirt particles can be released from the stator winding during the motor operation. If no suitable counter-measures are taken, these dirt particles can enter the clean room in which the memory discs are arranged. In the worst case, this leads to the destruction of the fixed-memory discs.